• Code F: A flat $150.00 fee for unlimited minutes (not available to businesses)
• Code M: A charge of $5, plus 21 cents a minute
• Code H: $40 for the first 600 minutes used, plus 19 cents for each additional minute.
• Code P: $64 for the first 1000 minutes used, plus 17 cents for each additional minute
• Code B: $150 for up to 2,000 minutes; $210 for up to 3,000 minutes, and $240 if over 3,000 minutes

No other codes should be accepted. Then prompt for a 5-digit customer account number (no leading zeros allowed) and error check value is valid. Re-prompt until a valid value is entered. This input should be read and error checked from within the main function. Next call display a menu of plan codes, along with descriptions of each, to the user. Prompt for the plan code and error check that the user entered a valid plan code (accepted in upper or lowercase). Re-prompt until a valid value is entered. If necessary (all plans except plan F), also prompt for the number of minutes used and error check that the number entered is not negative. Re-prompt until a valid value is entered.

Calculate the bill total and display the results. The output should display: the customer account number, the plan chosen in words, the number of minutes used (unless the plan chosen was F), and the total amount of bill. Display neatly
with descriptive text. After displaying the results, ask the user whether to execute the program again, and do so, as long as the user wishes to continue.
At a minimum, the program must implement three separate functions (in addition to main), as described on the next page:

• One function to read and validate the plan choice read and validate the number of minutes used.
• One function to calculate the amount of the bill and return the bill amount.
• One function to display the bill output.

The functions must use parameters to pass required data to each function. Remember to pass all input only parameters by value, and pass all output parameters by reference.

U can do what u did in the getPlan_Minutes function where you use a switch statement to determine the output. But, since you're using the 'plan' multiple times it would probably be better to just store into a string instead of repeatedly typing it all out with cout each time.